1. Field of the Invention
This invention relates to a device for use in conjunction with an oil filter to facilitate rapid cleaning and oil change of an associated engine and, optionally, to permit reconditioning of a suitable oil filter. This invention also relates to permanent or reusable oil filters for use with internal combustion engines. Finally, this invention relates to a method for changing motor oil and, optionally, flushing and cleaning the motor oil reservoir, crankcase components, and oil filter in an internal combustion engine.
2. Description of the relevant art
Filters capable of removing contaminants from organic liquids such as fuels and oils are well known. One such example, oil filters, are typically located in an oil circulation line of an internal combustion engine downstream of the associated oil pump. The function of the oil filter is to remove particulate and other contaminants from the lubricating oil in order to enhance engine life and performance.
The typical oil filter consists of a cylindrical housing having suitable means for permitting attachment of the filter to the engine block. The housing contains filtration media suitable for filtering particulates from the oil as it flows through the filter housing on its way back to the engine block. The attachment means, ordinarily located at one end of the filter housing, is adapted for mating contact with the engine block so as to provide two separate avenues of fluid communication: one between the oil pump discharge line and the filter inlet opening; and the other between the filter outlet opening and the internal lube oil passages leading to the various lubricating points in the engine. Connection between the filter outlet and the engine block is generally accomplished by means of a central opening in one end of the filter housing which is internally threaded to receive an externally threaded conduit protruding from the engine block. The oil from the engine generally enters the filter through a number of holes in the housing which surround the central opening. After passing through the filter, the oil reenters the engine block via the conduit. A gasket surrounding the housing perimeter outside the perimeter of the inlet holes seals the filter unit against the engine block.
During engine operation, particulate and other contaminants caused by the abrasive wear of the engine parts are circulated by the lubricating oil and collected in the filter. With continued use, the effectiveness of the filter gradually diminishes with corresponding increase in the resistance across the filtration media causing oil pressure upstream of the filter unit to increase and the down stream flow of oil to diminish. In most conventional automotive operations, once the upstream oil pressure reaches a predetermined level, a bypass valve either incorporated in the filter housing or in the engine block itself will open to relieve the pressure and restore oil flow. This allows unfiltered oil to reenter the engine block and travel to the lubricating points. Even though it is undesirable to lubricate with unfiltered oil, it is better than having no lubrication at all, as the latter situation would cause almost certain engine failure.
For optimum performance and engine longevity proper filtration of the engine lubrication oil is essential. In current practice, oil filters are replaced at regular intervals, usually concurrent with an oil change. Oil filters currently in use vary in size, shape and thread size to correspond with a particular engine. These are not readily interchangeable. Thus a variety of various sizes must be manufactured to make filters available for all makes and models of cars.
Disposal of the spent oil filters poses a large and environmentally sensitive problem. The number of passenger cars and light trucks registered in the United States in 1988 was 153 million. It is estimated that the average frequency of oil changes is 2.94 times per year for each vehicle. It is also estimated that the oil filter is changed during 90% of the oil changes. This amounts to the disposal of approximately 400 million oil filters in 1988 alone. These spent oil filters each containing residual waste oil find their way into the nation's trash adding to already critical waste disposal and pollution of the nation's land and water resources. Furthermore, these spent filters must be replaced with newly manufactured products causing an unnecessary waste of natural resources, such as metal for the housing material, cellulose materials for the filtration media, and the manpower required to produce them.
Thus it is desirable to provide a convenient, environmentally safe, no-mess alternative to conventional oil filter changes which eliminates or reduces the amount of waste and pollution generated by the discarding of disposable oil filters containing residual spent oil. It is also desirable to provide a method and device which provides an alternative to the use of disposable oil filters which is economical to the consumer and supports and complies with the spirit and intent of current and proposed legislation regarding waste reduction, pollution abatement and conservation of natural resources.